1. Field of the Invention
The instant invention relates generally to a composition for treating impotence in men that relieves erectile dysfunction and enhances sexual desire, and specifically to a composition for treating impotence by using fish roe either alone or in combination with yohimbine. The invention relates also to methods of preparing fish roe for use as a pharmaceutical product to treat impotence and for incorporation into the compositions of the present invention.
2. Description of the Prior Art
Therapies for treating impotence are known in the art. These include the compositions and treatment methods described below.
Hormonal Treatments (Androgens)
Testosterone and its derivatives are obtained only by prescription. They are administered orally or via injection, buccal tablets or other pharmaceutical dosage forms. The main use is for hypogonadism, male climactric and impotence. Testosterone also has other applications in medicine. As with other hormonal treatments, during administration of exogenous testosterone, endogenous testosterone release is inhibited through the negative feedback mechanism of pituitary lutenizing hormone (LH, or lutropin).
Large doses of exogenous androgens may suppress spermatogenesis through a negative feedback response by inhibition of pituitary follicle stimulating hormone (FSH, or follitropin). This characteristically results in inadequate endogenous testosterone production once exogenous testosterone administration is discontinued.
Testosterone and its derivatives have been used successfully to develop or to maintain sexual characteristics and other physiologic functions in androgen deficient males. However it is of no benefit to patients that are not androgen deficient as can be demonstrated by plasma testosterone levels.
Yohimbine
Yohimbine is an indolalkylamine alkaloid having the chemical formula C.sub.21 H.sub.26 O.sub.3 N.sub.2 and a molecular weight of 354.5. It is the principal alkaloid of the bark (yohimbehe) of the west African Corynanthe johimbe (Rubiaceae) tree. Other, informal names for yohimbine include quebrachine, methyl yohimbate and corynine.
Yohimbine is primarily an a.sub.2 adrenergic blocker, i.e., it blocks presynaptic a.sub.2 adrenoreceptors causing release of norepinephrine. Its peripheral autonomic nervous system effect is to increase parasympathetic (cholinergic) activity and to decrease sympathetic (adrenergic) activity. In male sexual performance, erection is linked to cholinergic activity which theoretically results in increased penile blood inflow, decreased penile blood outflow, or both, causing erectile stimulation without increasing sexual desire (Drug Facts and Comparison, p. 731h, April 1995).
Yohimbine has been successfully used to treat impotence in some patients, particularly those with conditions of vascular or diabetic origin. A typical effective dosage of yohimbine in such treatments is 18 mg/day. At such dosages, yohimbine is known to produce various side effects, for example, increased blood pressure and heart rate, paresthesias and others. These side effects make such dosages unsuitable for patients with renal disease, cardio-renal disorders, gastric or duodenal ulcerations, and for psychiatric and geriatric patients.
Papaverine
Papaverine injection is only available by prescription; generally it is not the treatment of choice for impotence patients. Papaverine has been used as an injection administered into the penis directly. Erection usually occurs within 5-15 minutes after injection. Papaverine injection causes pain and bruising at the site of injection. Persistent painful erection that occurs independently of sexual desire (priapism) is a side effect which often lasts from 5-7 hours causing embarrassment and discomfort to the patient. Fibrous growth in the penis tissue has also been reported.
Caverject
Caverject is a brand name marketed and available only by prescription. It is the synthetic version of alprostadil (prostaglandin E) which the body uses to help produce an erection. The medication is injected directly into the penis shortly before intercourse. It relaxes smooth muscle tissue in the penis which in turn enhances blood flow to the penis and causes erection. Caverject is often effective for men whose impotence is due to diabetic complications, anxiety or radical prostatectomy. One of the major drawbacks of caverject is that the subject, after injection, may have long lasting painful erection (priapism), which may last more than 6 hours and cause serious and permanent damage to the delicate spongy structure of the penis which may never again function properly.
Penile Implants
Penile implants, primarily made from silicone rubber, are surgically inserted in the shaft of the penis to make it sufficiently rigid for vaginal intercourse. Penile implant operations were first preformed in the 1960's and now some 30,000 men have the surgery each year. Penile implants come in different styles and sizes; semirigid, flexible rods or cylinders that are surgically inserted into both sides of the penis but do not get as hard as a natural erection. Men with this kind of implant have permanent enlargement (erection).
Inflatable Implants
Inflatable implants are another type of penile implant. They consist of twin cylinders connected to a pump and a fluid-filled reservoir. The cylinders are inserted in the penis, the pump concealed in the scrotum and the reservoir in the abdominal cavity. When the pump is squeezed, the fluid is forced out of the reservoir into the cylinders, causing an erection. When the pump is squeezed again, the fluid is released back into the reservoir, lowering the erection.
Implants have their own drawbacks; they are uncomfortable, require surgery which may have serious complications, are very expensive, and not every man is a candidate for penile implantation. Most men look for less invasive remedies.
In addition to the treatments described above, the following substances are often misconceived as sex stimulants.
Marijuana
Some people think marijuana use will cause sexual stimulation, however marijuana is more likely to be a sexual depressant and is also illegal to possess or use in many states.
Alcohol
Alcohol is also perceived as a sexual stimulant but is actually a sexual depressant and results in liver damage when consumed in quantity.
Amyl Nitrate
Amyl nitrate has been used (as an inhalant) because of its peripheral vasodilation effect which is perceived as a sexual stimulant, but actually is not. Its side effects are of serious concern, particularly in men and women with hypertension or over the age of 40.